Method of manufacturing cigarette paper



Patented Jan. 24, 1939 PATENT OFFICE METHOD OFlV IANUFACTURING CIGARETTEPAPER- Roger Braunstein, Paris, France, assignor to Societe Anonyme desBraunstein Freres, Paris, France, a company of France AnciensEtablissements No Drawing. Application February 3, 1936, Se-

rial No. 62,225.

2 Claims.

In the French Patent No. 732,872, of March 9, 1932, there is described aprocess in which stearic acid is incorporated into cigarette paper, byproducing, in the paper pulp, a decomposition which 5 disengages thedesired acid. Preferably, there is added a soluble stearate the acid ofwhich has been precipitated by addition of oxalic acid until a weakacidity is obtained (pH averaging 6). In

this patent, it was advised to operate in such 10 manner as to leave inthe cigarette paper A an amount of stearic acid averaging from 2 to 8%of the total weight of the paper.

It may be of interest to reduce the amount of stearic acid in the finalproduct. However, this reduction may tend to impair the whiteness andthe opacity of the paper, these being qualities which are requested onmany markets. It is therefore necessary to compensate for thismodification by a corresponding addition of loading 0 materials orfillers. These loading materials or fillers must comply with severalconditions. For instance, they must be compatible with oxalic acid orany other acid that is used for the precipitation of stearic acid, thatis to say these loading materials must not react on the acid abovementioned. Furthermore, they must not interfere with the combustion ofthe paper, for instance they must not have a reducing action, in orderto avoid incomplete combustions of the cellulosic fibers or of theadditional products, such as stearin, since the products resulting fromincomplete combustion, for instance acroleine and similar bodies areevil smelling.

It is therefore necessary to avoid the introduction of calcium ormagnesium oxalates in addition to the amounts produced by thealkali-earth salts of waters because oxalates are reducing bodies. 0nthe other hand, the utilization of products facilitating a very quickcombustion, such as chlorates or nitrates is not advisable because thesebodies also give evil smelling combustion products.

The object of the present invention is toprovide a process owing towhich, on the one hand, I reduce the amount of stearic acid introducedin any suitable manner but preferably through a decomposition in themass of the paper pulp, and, on the other hand, I add loading materialswhich do not decompose under the efiect of the temperature, or which,whereas being decomposed, do not yield reducing products. In the lattercase, the inflow of air to the ignition zone is such that the productsof combustion are extremely similar to the products of a theoreticallycomplete combustion, to wit carbon dioxide and odourless products.

' Among the loading materials which comply with these conditions andwhich will be chosen In France February 11, 1935 according to thecircumstances, I may cite kaolins of more or less finely dividedtexture, white metallic oxides, finely divided silicas, asbestos, etc.

An especially advantageous embodiment of the invention consists inmaking use, as loading mate- 5 rial, of titanium dioxide. The producthas an excellent covering power and it compensates for the loss ofopacity which results from the reduction of the percentage of stearicacid. Due to this reduction of the amount of acid present in the 10paper, the latter, while keeping its good properties of elongation, hasits breaking strength increased. The weight of paper per square meter isnot substantially increased. Practically, the cigarette does not take ayellow colour when in use. Furthermore the simultaneous presence ofstearic acid and titanium oxide gives a special advantage, which is thefollowing: stearic acid increases the retaining coefiicient of therelatively expensive loading material consisting of titanium oxide.

I shall indicate, merely by way of example, that ,the percentage ofstearic acid precipitated in the paper may be reduced to about 0.8% andthat a good proportion of titanium oxide in the paper is about 2%.

The loading matter, for instance titanium oxide, is preferably added tothe paper pulp while the latter is in the refining device.

The present invention further includes the manfacturing process in whichthe steps above mentioned are combined with that consisting in whollyeliminating, or at least eliminating as completely as possible, thecalcium oxalate that comes from the calcareous salts present in water.For this purpose, I may previously decalcify the waters serving to thetreatment of the paper 'pulp, for instance as explained in the Frenchpatent above referred to, by precipitating the calcareous salts into thestate of insoluble calcium oxalate or I may choose natural waters havinga low hydrotimetric degree. 40

In a general manner, I do not wish to be limited to the specific dataabove disclosed as there might be changes made therein without departingfrom the principle of the present invention as comprehended within thescope of the appended claims.

What I claim is:

1. A process for the manufacture of cigarette paper from paper pulp,which comprises incorporating in said paper pulp stearic acid andtitanium dioxide, in such amounts that the final percentages thereof inthe cigarette paper are substantially equal to 0.8 and 2 respectively.

2. A cigarette paper which contains stearic acid and titanium dioxide inamounts substantially equal to 0.8 and 2 per cent, respectively.

ROGER BRAUNSTEIN-

